1. Field of the Invention
The present invention relates to a capsule sealing apparatus, and more particularly to an apparatus for sealing the seams between the caps and the bodies of capsules containing powdery, granular, or liquid pharmaceutics and foodstuff.
2. Description of the Prior Art
It is known in the art to charge powdery, granular, or liquid pharmaceutics in capsules made of hard gelatin so that patients can swallow with ease. The capsules of hard gelatin have a hollow cylindrical body and a hollow cylindrical cap having a larger diameter than the body. The body is fitted in the cap after contents are charged in the body.
Depending upon the nature of the content, it is necessary to close the body with the cap liquid-tightly. If the joint between the cap and the body becomes loose after the content is charged, the content is likely to leak, and/or dirt and germs are likely to enter the capsules. This causes fatal unsanitary problems.
The inventors have made an invention relating to an apparatus for automatically sealing charged capsules, which is disclosed in Japanese Laid-Open Patent Publication (Kokai) No. 60-190964. This prior capsule sealing apparatus includes a plurality of plate-like slats on which capsules are individually mounted. Each capsule is made of a cap and a body, and during travel of the conveyor device the seam between the cap and body is sealed with a sealing medium (hereinafter referred to as "sealer") that is picked up and coated by a coating disc. The conveyor is rotated by means of endless chains or the like whereby the circulating route of the slats includes horizontally moving areas where capsules are horizontally maintained, and vertically moving areas where they take a vertical position. In the vertically moving areas a suitable means is required for preventing the capsules from falling off the slats. Such preventing means need direct contact with the capsules. If the sealer on the capsules is not dried, the sealing coat is likely to be broken. In addition, the prior art sealing apparatus uses a separate drying device. Thus, as a whole the sealing unit becomes large in size, occupying a large installation site, and the structure becomes complicated. Because of the limited space, the prior art sealing apparatus is not allowed to employ more than one coating stations. In fact, however, the single coating station is not sufficient to obtain a strong seal between the caps and the bodies of capsules.
The inventors have made another proposal which is disclosed in Japanese Laid-Open Patent Publication (Kokai) No. 61-68050. This prior art invention provides a capsule conveyor device on which capsules are at a slant in the direction in which they are conveyed, thereby ensuring that capsules of various sizes can be sealed. However, this prior invention has not solved how to coat a sealer adequately along the seams between the caps and bodies of capsules during travel.